// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Copyright (c) 1998-2001 Vojtech Pavlik
 *
 *  Based on the work of:
 *      Steffen Schwenke
 */

/*
 * TurboGraFX parallel port interface driver for Linux.
 */

#include <linux/kernel.h>
#include <linux/parport.h>
#include <linux/input.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/slab.h>

MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
MODULE_DESCRIPTION("TurboGraFX parallel port interface driver");
MODULE_LICENSE("GPL");

#define TGFX_MAX_PORTS          3
#define TGFX_MAX_DEVICES        7

struct tgfx_config {
        int args[TGFX_MAX_DEVICES + 1];
        unsigned int nargs;
};

static struct tgfx_config tgfx_cfg[TGFX_MAX_PORTS];

module_param_array_named(map, tgfx_cfg[0].args, int, &tgfx_cfg[0].nargs, 0);
MODULE_PARM_DESC(map, "Describes first set of devices (<parport#>,<js1>,<js2>,..<js7>");
module_param_array_named(map2, tgfx_cfg[1].args, int, &tgfx_cfg[1].nargs, 0);
MODULE_PARM_DESC(map2, "Describes second set of devices");
module_param_array_named(map3, tgfx_cfg[2].args, int, &tgfx_cfg[2].nargs, 0);
MODULE_PARM_DESC(map3, "Describes third set of devices");

#define TGFX_REFRESH_TIME       HZ/100  /* 10 ms */

#define TGFX_TRIGGER            0x08
#define TGFX_UP                 0x10
#define TGFX_DOWN               0x20
#define TGFX_LEFT               0x40
#define TGFX_RIGHT              0x80

#define TGFX_THUMB              0x02
#define TGFX_THUMB2             0x04
#define TGFX_TOP                0x01
#define TGFX_TOP2               0x08

static int tgfx_buttons[] = { BTN_TRIGGER, BTN_THUMB, BTN_THUMB2, BTN_TOP, BTN_TOP2 };

static struct tgfx {
        struct pardevice *pd;
        struct timer_list timer;
        struct input_dev *dev[TGFX_MAX_DEVICES];
        char name[TGFX_MAX_DEVICES][64];
        char phys[TGFX_MAX_DEVICES][32];
        int sticks;
        int used;
        int parportno;
        struct mutex sem;
} *tgfx_base[TGFX_MAX_PORTS];

/*
 * tgfx_timer() reads and analyzes TurboGraFX joystick data.
 */

static void tgfx_timer(struct timer_list *t)
{
        struct tgfx *tgfx = timer_container_of(tgfx, t, timer);
        struct input_dev *dev;
        int data1, data2, i;

        for (i = 0; i < 7; i++)
                if (tgfx->sticks & (1 << i)) {

                        dev = tgfx->dev[i];

                        parport_write_data(tgfx->pd->port, ~(1 << i));
                        data1 = parport_read_status(tgfx->pd->port) ^ 0x7f;
                        data2 = parport_read_control(tgfx->pd->port) ^ 0x04;    /* CAVEAT parport */

                        input_report_abs(dev, ABS_X, !!(data1 & TGFX_RIGHT) - !!(data1 & TGFX_LEFT));
                        input_report_abs(dev, ABS_Y, !!(data1 & TGFX_DOWN ) - !!(data1 & TGFX_UP  ));

                        input_report_key(dev, BTN_TRIGGER, (data1 & TGFX_TRIGGER));
                        input_report_key(dev, BTN_THUMB,   (data2 & TGFX_THUMB  ));
                        input_report_key(dev, BTN_THUMB2,  (data2 & TGFX_THUMB2 ));
                        input_report_key(dev, BTN_TOP,     (data2 & TGFX_TOP    ));
                        input_report_key(dev, BTN_TOP2,    (data2 & TGFX_TOP2   ));

                        input_sync(dev);
                }

        mod_timer(&tgfx->timer, jiffies + TGFX_REFRESH_TIME);
}

static int tgfx_open(struct input_dev *dev)
{
        struct tgfx *tgfx = input_get_drvdata(dev);

        scoped_guard(mutex_intr, &tgfx->sem) {
                if (!tgfx->used++) {
                        parport_claim(tgfx->pd);
                        parport_write_control(tgfx->pd->port, 0x04);
                        mod_timer(&tgfx->timer, jiffies + TGFX_REFRESH_TIME);
                }

                return 0;
        }

        return -EINTR;
}

static void tgfx_close(struct input_dev *dev)
{
        struct tgfx *tgfx = input_get_drvdata(dev);

        guard(mutex)(&tgfx->sem);

        if (!--tgfx->used) {
                timer_delete_sync(&tgfx->timer);
                parport_write_control(tgfx->pd->port, 0x00);
                parport_release(tgfx->pd);
        }
}



/*
 * tgfx_probe() probes for tg gamepads.
 */

static void tgfx_attach(struct parport *pp)
{
        struct tgfx *tgfx;
        struct input_dev *input_dev;
        struct pardevice *pd;
        int i, j, port_idx;
        int *n_buttons, n_devs;
        struct pardev_cb tgfx_parport_cb;

        for (port_idx = 0; port_idx < TGFX_MAX_PORTS; port_idx++) {
                if (tgfx_cfg[port_idx].nargs == 0 ||
                    tgfx_cfg[port_idx].args[0] < 0)
                        continue;
                if (tgfx_cfg[port_idx].args[0] == pp->number)
                        break;
        }

        if (port_idx == TGFX_MAX_PORTS) {
                pr_debug("Not using parport%d.\n", pp->number);
                return;
        }
        n_buttons = tgfx_cfg[port_idx].args + 1;
        n_devs = tgfx_cfg[port_idx].nargs - 1;

        memset(&tgfx_parport_cb, 0, sizeof(tgfx_parport_cb));
        tgfx_parport_cb.flags = PARPORT_FLAG_EXCL;

        pd = parport_register_dev_model(pp, "turbografx", &tgfx_parport_cb,
                                        port_idx);
        if (!pd) {
                pr_err("parport busy already - lp.o loaded?\n");
                return;
        }

        tgfx = kzalloc_obj(*tgfx);
        if (!tgfx) {
                printk(KERN_ERR "turbografx.c: Not enough memory\n");
                goto err_unreg_pardev;
        }

        mutex_init(&tgfx->sem);
        tgfx->pd = pd;
        tgfx->parportno = pp->number;
        timer_setup(&tgfx->timer, tgfx_timer, 0);

        for (i = 0; i < n_devs; i++) {
                if (n_buttons[i] < 1)
                        continue;

                if (n_buttons[i] > ARRAY_SIZE(tgfx_buttons)) {
                        printk(KERN_ERR "turbografx.c: Invalid number of buttons %d\n", n_buttons[i]);
                        goto err_unreg_devs;
                }

                tgfx->dev[i] = input_dev = input_allocate_device();
                if (!input_dev) {
                        printk(KERN_ERR "turbografx.c: Not enough memory for input device\n");
                        goto err_unreg_devs;
                }

                tgfx->sticks |= (1 << i);
                snprintf(tgfx->name[i], sizeof(tgfx->name[i]),
                         "TurboGraFX %d-button Multisystem joystick", n_buttons[i]);
                snprintf(tgfx->phys[i], sizeof(tgfx->phys[i]),
                         "%s/input%d", tgfx->pd->port->name, i);

                input_dev->name = tgfx->name[i];
                input_dev->phys = tgfx->phys[i];
                input_dev->id.bustype = BUS_PARPORT;
                input_dev->id.vendor = 0x0003;
                input_dev->id.product = n_buttons[i];
                input_dev->id.version = 0x0100;

                input_set_drvdata(input_dev, tgfx);

                input_dev->open = tgfx_open;
                input_dev->close = tgfx_close;

                input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
                input_set_abs_params(input_dev, ABS_X, -1, 1, 0, 0);
                input_set_abs_params(input_dev, ABS_Y, -1, 1, 0, 0);

                for (j = 0; j < n_buttons[i]; j++)
                        set_bit(tgfx_buttons[j], input_dev->keybit);

                if (input_register_device(tgfx->dev[i]))
                        goto err_free_dev;
        }

        if (!tgfx->sticks) {
                printk(KERN_ERR "turbografx.c: No valid devices specified\n");
                goto err_free_tgfx;
        }

        tgfx_base[port_idx] = tgfx;
        return;

 err_free_dev:
        input_free_device(tgfx->dev[i]);
 err_unreg_devs:
        while (--i >= 0)
                if (tgfx->dev[i])
                        input_unregister_device(tgfx->dev[i]);
 err_free_tgfx:
        kfree(tgfx);
 err_unreg_pardev:
        parport_unregister_device(pd);
}

static void tgfx_detach(struct parport *port)
{
        int i;
        struct tgfx *tgfx;

        for (i = 0; i < TGFX_MAX_PORTS; i++) {
                if (tgfx_base[i] && tgfx_base[i]->parportno == port->number)
                        break;
        }

        if (i == TGFX_MAX_PORTS)
                return;

        tgfx = tgfx_base[i];
        tgfx_base[i] = NULL;

        for (i = 0; i < TGFX_MAX_DEVICES; i++)
                if (tgfx->dev[i])
                        input_unregister_device(tgfx->dev[i]);
        parport_unregister_device(tgfx->pd);
        kfree(tgfx);
}

static struct parport_driver tgfx_parport_driver = {
        .name = "turbografx",
        .match_port = tgfx_attach,
        .detach = tgfx_detach,
};

static int __init tgfx_init(void)
{
        int i;
        int have_dev = 0;

        for (i = 0; i < TGFX_MAX_PORTS; i++) {
                if (tgfx_cfg[i].nargs == 0 || tgfx_cfg[i].args[0] < 0)
                        continue;

                if (tgfx_cfg[i].nargs < 2) {
                        printk(KERN_ERR "turbografx.c: at least one joystick must be specified\n");
                        return -EINVAL;
                }

                have_dev = 1;
        }

        if (!have_dev)
                return -ENODEV;

        return parport_register_driver(&tgfx_parport_driver);
}

static void __exit tgfx_exit(void)
{
        parport_unregister_driver(&tgfx_parport_driver);
}

module_init(tgfx_init);
module_exit(tgfx_exit);